In scroll compressors it is necessary or at least highly desirable to provide an axial compliance mechanism which effects proper sealing of the wrap tips against the adjacent scroll base even though pressures of several hundred psi are typically developed in the pressure continuum, i.e., the compression pockets which are continuously formed, compressed, discharged and reformed between the scrolls. This mechanism, most often comprises an axial compliance pressure chamber which is sealed to ambient pressures by one or more annular, elastomeric seals which bear and seal against portions of the orbiting scroll base and fixed portions of the compressor housing. This sealing structure necessarily requires an orbital rubbing of the seal against at least one of these structures. The said pressure chamber is designed to communicate with an intermediate pressure region of said continuum and thereby exert forces against the axially outer surface, i.e., low pressure side of the base of the orbiting scroll to significantly counteract the axial forces generated in the pressure continuum which tend to axially separate the scrolls. One of the greatest difficulties encountered with the use of such a chamber is the problem of maintaining its seal during the axial compliance and orbital movements of the scroll over the enormous number of orbital cycles of the compressor during its lifetime.
Also, in scroll compressors, the high pressure pockets of the pressure continuum are typically responsible for imparting strong forces, i.e., tangential, radial, or lateral against the wrap of the orbiting scroll which tend to tip the scroll on its longitudinal axis. Such tipping-can place the chamber seal in alternating compressed and relaxed conditions, which, in combination with a simultaneous frictional, orbital sliding contact of the seal with metal can lead to premature failure of the seal and loss of sealing between the wrap walls and between each wrap tip and the juxtaposed base of the other scroll, and thus a reduction in compressor efficiency.